package com.gt.utils;

import com.alibaba.fastjson.JSON;
import com.gt.contant.AjaxCode;
import com.gt.exception.ServiceException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.StringUtils;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.Enumeration;
import java.util.Properties;

@Slf4j
public class PropertiesUtils {
	// 根据key读取value
	public static String readValue(String filePath, String key) {
		Properties props = new Properties();
		try {
			InputStream in = new BufferedInputStream(new FileInputStream(filePath));
			props.load(in);
			String value = props.getProperty(key);
			System.out.println("PropertiesUtils.readValue====:" + key + "_" + value);
			return value;
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

	// 读取properties的全部信息
	public static void readProperties(String filePath) {
		Properties props = new Properties();
		try {
			InputStream in = new BufferedInputStream(new FileInputStream(
					filePath));
			props.load(in);
			Enumeration en = props.propertyNames();
			while (en.hasMoreElements()) {
				String key = (String) en.nextElement();
				String Property = props.getProperty(key);
				System.out.println(key + Property);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	// 写入properties信息
	public static void writeProperties(String filePath, String parameterName,
			String parameterValue) {
		Properties prop = new Properties();
		try {
			InputStream fis = new FileInputStream(filePath);
			// 从输入流中读取属性列表（键和元素对）
			prop.load(fis);
			// 调用 Hashtable 的方法 put。使用 getProperty 方法提供并行性。
			// 强制要求为属性的键和值使用字符串。返回值是 Hashtable 调用 put 的结果。
			OutputStream fos = new FileOutputStream(filePath);
			prop.setProperty(parameterName, parameterValue);
			// 以适合使用 load 方法加载到 Properties 表中的格式，
			// 将此 Properties 表中的属性列表（键和元素对）写入输出流
			prop.store(fos, "Update '" + parameterName + "' value");
		} catch (IOException e) {
			System.err.println("Visit " + filePath + " for updating "
					+ parameterName + " value error");
		}
	}

	public static void renderJson(HttpServletRequest request, HttpServletResponse response, Object jsonObject) {
		PrintWriter writer = null;
		String origin = request.getHeader("Origin");
		if(StringUtils.isEmpty(origin)){
			origin = StringUtils.isEmpty(request.getHeader("Referer"))?"*":request.getHeader("Referer");
		}
		try {
			response.setContentType("application/json;charset=UTF-8");
			response.setCharacterEncoding("UTF-8");
			response.setHeader("Access-Control-Allow-Credentials", "true");
			response.setHeader("Access-Control-Allow-Origin", origin);
			response.setHeader("Access-Control-Allow-Methods", "POST, GET, PATCH, DELETE, PUT, OPTIONS"); // 允许的请求方式
			response.setHeader("Access-Control-Max-Age", "3600"); // 预检请求的有效期
			response.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, token");
			writer = response.getWriter();
			log.info("请求来源：{}",origin);
			log.info("往页面写数据：{}",JSON.toJSONString(jsonObject));
			writer.write(JSON.toJSONString(jsonObject));
		} catch (IOException var3) {
			throw new ServiceException(AjaxCode.WRITE_ERROR);
		}finally {
			if (writer != null) {
				writer.close();
			}
		}
	}
}
